Flooring material, comprising board shaped floor elements which are intended to be joined vertically

ABSTRACT

Flooring material including floor boards ( 1 ) with an essentially square, rectangular or rhomboidal shape. The floor boards ( 1 ) are provided with edges ( 2 ), a horizontal lower side ( 5 ) and a horizontal decorative upper surface ( 3 ). The floor boards ( 1 ) are provided with lower joining lips ( 10 ) at two adjacent edges ( 2 ) while the two remaining edges ( 2 ) are provided with upper joining lips ( 20 ). The lower joining lips ( 10 ) are provided essentially vertical lower lip surfaces  911 ) arranged parallel to the closest edge ( 2 ). The lower lip surfaces ( 11 ) are intended to interact with mainly vertical upper lip surfaces ( 21 ) arranged on the upper joining lips ( 20 ). Two joined adjacent floor boards ( 1 ) are hereby locked together in a horizontal direction. The joining lips ( 10  and  20  respectively) are furthermore provided with one or more heels ( 31 ) intended to snap join with recesses ( 32 ) adapted thereto which, by being provided with essentially horizontal locking surfaces, limits vertical movement between two joined adjacent floor boards ( 1 ).

The present invention relates to a flooring material comprising boardshaped floor elements which are intended to be joined vertically.

Prefabricated floor boards which are provided with tongue and groove atthe edges are well known today. As these are rather easy to install,this can be achieved by the average handy man. Such floors can be madeof solid wood, particle board or fibre board. These floor boards aremost often provided with a top surface, such as lacquer or some kind oflaminate. The board are most often joined by being glued together viatheir tongue and groove. The most common types of floor boards are,however, burdened with the disadvantage to form gaps of varying widthbetween the floor boards if the installer is not thorough enough. Dirtwill accumulate in such gaps. Moisture will furthermore enter the jointswhich will cause the core to expand in cases where it is made of solidwood, fibre board or particle board which usually is the case. Thisexpansion will cause the top surface to rise closest to the joint, whichradically decreases the useful life of the floor due to increased wearon the protruding edges of the floor board. In order to avoid this typeof gaps it is known to use different type of tensioning devices used forclamping the floor boards together during installation. This operationis, however, rather awkward and it is desirable to achieve a floor boardwith a joint which is self-orienting and thereby automatically will findits correct position. It would also be possible to use such a jointwithout having to use glue.

The above mentioned problems have been solved through the presentinvention whereby a floor that is easy to install has been achieved.Accordingly, the invention relates to a flooring material includingfloor boards with an essentially square, rectangular or rhomboidalshape. The floor boards are provided with edges, a horizontal lower sideand a horizontal decorative upper surface. The floor boards are providedwith lower joining lips at two adjacent edges while the two remainingedges are provided with upper joining lips. The invention ischaracterised in that the lower joining lips are provided withessentially vertical lower lip surfaces arranged parallel to the closestedge which lower lips surfaces are intended to interact with mainlyvertical upper lip surfaces arranged on the upper joining lips. Twojoined adjacent floor boards are hereby locked together in a horizontaldirection. The joining lips are furthermore provided with one or moreheels intended to snap-join with recesses adapted thereto which, bybeing provided with essentially horizontal locking surfaces, limitsvertical movement between two joined adjacent floor boards.

The joint between two floor boards joined together, preferably includesfitting surfaces which are comprised by the horizontal locking surfaceson the recesses and the heels, the vertical upper lip surfaces and upperfitting surfaces. The joint between two floor boards joined togethersuitably also includes cavities.

According to one embodiment of the invention the heel is constituted bya resilient part which is arranged in a cavity. The recess isalternatively constituted by a resilient part which is arranged in acavity. Such a resilient part may suitably be constituted by an extrudedthermoplastic profile, a profile made of thermosetting resin or anextruded or a cold forged profile made of metal or the like.

These resilient parts may be handled in different ways. One suitable wayis to pre-mount these into cavities intended for the purpose. Theresilient part will hereby be in the correct position when the floor isto be installed. The material chosen will, however, be limited somewhatsince some of the floor boards will have to be cut in connection to theinstallation as the floor board and the resilient part will have to becut simultaneously. Thinner profiles made of brittle materials, such asthermosetting resins, might for example shatter if cut with an ordinaryfog saw, while for example steel is practically impossible to cut withsuch a tool. Since the floor board itself usually comprises a core offibreboard or particleboard with a surface of thermosetting laminate thechoice of cutting tools will be somewhat limited. Aluminium, or athermoplastic material such as polypropylene, polyethylene, poly amideor polystyrene, advantageously containing a filler, is thereforesuitable where a pre-assembled resilient part is desired. Pre-assembledresilient parts does suitably have a length only a bit shorter than theside on which they are mounted. A prevalent dimension on the floor boardis 200×1200 mm.

It is also possible to mount the resilient part during the installationof the floor. The choice of material in the resilient parts will herebybe more free as they may be manufactured in different, and shorterlengths. It hereby becomes possible to choose spring steel which willprovide an excellent locking. Suitable lengths of post-assembledresilient part may be from a few centimeters to a couple of decimeters.

The flooring material comprising the above floor board is very suitedwhen installing floors where no glue is to be used. It is, of course,possible to utilise glue or adhesive tape to make the installationirreversibly permanent. The glue or tape is then suitably applied in, orin connection to, possible cavities before joining the floor boards.

Floor boards according to present invention are, unlike common types offloor boards, joined by being pressed downwards. Commonly known floorboards are assembled horizontally by being forced or knocked together.Some known floor boards are assembled by being turned or prized intoposition. These known floor boards are guided vertically, and in a fewcases also horizontally, on a great number of variations on thetongue-and-grove theme. It is very difficult to apply sufficienthorizontal force manually at floor level whereby different types oftensioning devices are essential when installing such floors. Theinstaller will only have to apply some of his body weight over the jointand the floor boards will snap together, when installing floorsaccording to the present invention. It is hereby becomes possible walkthe floor boards into position once they are placed correctly.

It is also possible to install the floor standing up by using verysimple tools, for example a couple of rods with a suction cup at thelower ends. It would thereby be possible to install the floor withouthaving to crawl on ones knees. Industrial injuries such as back and kneeproblems are very common among floor installers.

The invention is explained further together with enclosed drawingsshowing different embodiments of the invention whereby,

FIG. 1 shows an embodiment of two opposite edges 2 of a floor board 1according to the present invention. These are shown in cross-section inorder to facilitate understanding of the invention.

FIGS. 2a and 2 b show a second embodiment of the invention. FIG. 2ashows, in cross-section, the two adjacent edges 2 of two floor boards 1before assembly while FIG. 2b shows the same two floor boards 1 afterbeing joined.

FIGS. 3a and 3 b show another embodiment of the invention. FIG. 3ashows, in cross-section, the two adjacent edges 2 of two floor boards 1before assembly while FIG. 3b shows the same floor boards 1 after beingjoined.

FIG. 4 shows a geometric variation of the embodiment of FIGS. 3a and 3b.

FIG. 5 shows a another geometric variation of the embodiment of FIGS. 3aand 3 b.

FIG. 1 shows parts of a flooring material comprising floor boards 1. Thefloor boards 1 are provided with edges 2, a horizontal lower side 5 anda horizontal upper decorative surface 3. The floor boards 1 are at twoadjacent edges 2 provided with lower joining lips 10 (only one shown)while the two remaining edges 2 are provided with upper joining lips 20(only one shown). The lower joining lips 10 are provided with mainlyvertical lower lip surfaces 11 arranged parallel to the closest edge 2.The lower lip surfaces 11 are intended to interact with mainly verticalupper lip surfaces 21 arranged on the upper joining lips 20 so that twojoined adjacent floor boards 1 are locked together in a verticaldirection. The joining lips 10 and 20 respectively are furthermoreprovided with each one heel 31 with a matching recess 32. A verticalmovement between two joined adjacent floor boards 1 is limited since therecess 32 and heel 31 respectively are provided with essentiallyhorizontal locking surfaces. The joining surfaces are also provided withfitting surfaces 3′ in order to avoid unintended gaps in the joint. Thegeometry of the joining edges are only shown schematically and may, ofcourse, be changed in many ways within the scope of the invention.

According to one embodiment of a floor board 1 according to the presentinvention, the floor boards 1 includes a core which is covered with anupper decorative surface 3. The core most often consists of woodparticles or fibre bonded together with glue or resin. Since the corematerial is sensitive to moisture it may be advantageous to treat thearea closest to the joint if the floor is to be exposed to moisture.This treatment may suitably include resin, wax or some kind of lacquer.It will not be necessary to treat the joint if the floor boards 1 are tobe glued since the glue itself will protect the joint from moisturepenetration. The decorative upper surface consists of a decorative paperimpregnated with melamine-formaldehyde resin. One or more layers of socalled overlay paper of α-cellulose, impregnated withmelaimine-formaldehyde resin is suitably placed on top of the decorativepaper. One or more of the above layers may be sprinkled with hardparticles, of for example α-aluminium oxide, silicon carbide or siliconoxide in connection to the impregnation in order to improve the abrasionresistance. The paper impregnated with resin is cured before, or inconnection to applying it to the core. The paper layers are suitablylaminated together before they are applied to the core in cases wherethe upper decorative surface 3 is constituted by more than one paperlayers. The lower side 5 may suitably be coated with a lacquer or aresin impregnated paper. According to another alternative embodiment ofthe invention the core of the floor board 1 is constituted by a mixtureof 4 -6 parts by weight of particles such as wood fibre, with an averageparticle size in the range 50 μm-3000 μm which is agglomerated with 4-6parts by weight of a thermoplastic polymer. The particles may partly orcompletely be constituted by another organic material such as bark,flax, straw, corn starch, fruit stones or the like. It is also possibleto partly or completely replace the organic particles with inorganicones such as stone dust, sand, lime, mica or the like.

The thermoplastic material is suitably constituted by a poly olefin suchas polyethylene, polypropylene, or polybutene but can also beconstituted by others such as polystyrene, acrylnitril-butadiene-styrenecopolymer, poly amid, polyvinyl chloride or poly carbonate.

Additives might be added to the material in order to adapt the elasticand acoustic properties of the core to the desired one. Among suchadditives can mentioned ethyl-vinyl-acetate, di-ethyl-phthalate,di-isobutyl-phthalate or epoxidated organic oils.

Among possible upper surfaces to the core specified above may bementioned thermosetting laminates including at least a decorative paperimpregnated with melamine-formaldehyde resin. Overlay paper and hardparticles may be added to this as described earlier in the presentapplication. The upper decorative surface may also be constituted by anacrylic foil, an acrylic lacquer and combinations thereof. It might alsobe constituted by a foil or a lacquer of poly olefins or poly olefinderivatives.

An adhesion problem between the different materials included in thefloor board might occur in certain combinations. It is possible toovercome these problems which normally present themselves asde-lamination problems, low impact strength or blistering, by adding0.01-1 part of dendritic macromolecules with a combination of chainterminators adapted to the characteristic materials of the floor boardin order to increase the chemical bond between the different materials.It is also possible to coat a decorative surface with an acrylic lacquercontaining, or being sprinkled with, hard particles of a-aluminiumoxide, silicon carbide or silicon oxide. The coating is most oftenachieved through use of a roller or through curtain coating. Amongsuitable acrylic lacquers can be mentioned radiation curing ones whichare cured with electron beam or ultraviolet light forming free radicalsin the uncured lacquer.

The FIGS. 2a and 2 b show a second embodiment of the invention. FIG. 2ashows in cross-section the adjacent edges 2 of two floor boards beforejoining while FIG. 2b shows the same after being joined. The embodimentshown is mainly the same as the one shown in FIG. 1. The embodimentshown in FIG. 2a-b is, however, in addition provided with cavities 6(FIG. 2b ) and a resilient part 7. The cavities 6 can for example befound in the finished joint between the contact surfaces that are formedbetween the horizontal locking surfaces on the recess 32 and the heel31, the vertical upper lip surface 21 and the lower lip surface 11together with the upper fitting surfaces 3′. The resilient part 7 isplaced in a cavity 6. The resilient part 7 forms a resilient recess 23and a resilient lower lip surface 11. The cavities 6 reduces thenegative effects loose particles might have, which loose particlesotherwise might cause undesired gaps in the upper part of the joint. Thecross-section geometry of the joint is only shown schematically focusingon the interaction between the different surfaces in order to facilitateunderstanding of the invention. Then invention is not limited to theembodiment as it can be varied within the scope of the invention.

The FIGS. 3a and 3 b show another embodiment of the invention. FIG. 3ashows, in cross-section the adjacent edges 2 of two floor boards 1before joining while FIG. 3b shows the same after joining. Theembodiment shown in FIGS. 3a-b is essentially the same as the one shownin FIG. 1. The embodiment shown in FIG. 3a-b is however also providedwith cavities 6 (FIG. 3b ). The cavities 6 can for example be found inthe finished joint between the contact surfaces that are formed betweenthe horizontal locking surfaces on the recess 32 and the heel 31, thevertical upper lip surface 21 and the lower lip surface 11 together withthe upper fitting surfaces 3′. The cavities 6 reduces the negativeeffects loose particles might have, which loose particles otherwisemight cause undesired gaps in the upper part of the joint. Thecross-section geometry of the joint is only shown schematically focusingon the interaction between the different surfaces in order to facilitateunderstanding of the invention. The invention is not limited to theembodiment as it can be varied within the scope of the invention.

Recesses of a greater depth, as shown in FIGS. 3a and 3 b, isadvantageously achieved by means of laser cutting or broaching. Moreshallow recesses, such as the ones shown in FIGS. 1 and 2a-b may beachieved by more traditional methods such as milling.

FIG. 4 shows a geometric variation of the embodiment shown in FIGS. 3a-3b. FIG. 4 shows in cross-section the adjacent edges 2 of two floorboards 1 after being joined. The embodiment shown in FIG. 4 isessentially the same as the one shown in FIGS. 3a-3 b . The embodimentshown in FIG. 4 is, however, provided with somewhat inclined verticalsurfaces on the recess 32 and the heel 31. The vertical surfaces of thecavity 6′ is furthermore somewhat inclined while the height of thecavity 6′ is increased and the depth is reduced. The height of the upperand the lower vertical lip surface 21 and 11 respectively is at the sametime reduced while the height of the cavity 6″ also is reduced. Thegeometry of the joint is hereby made more open so it will possible tomanufacture by traditional methods such as milling.

FIG. 5 shows another geometric variation of the embodiment shown inFIGS. 3a-3 b . FIG. 5 shows in cross-section the adjacent edges 2 of twofloor boards 1 after being joined. The embodiment shown in FIG. 5 isessentially the same as the one shown in FIGS. 3a-3 b . The embodimentshown in FIG. 5 is, however, provided with a cavity 6′ with a reduceddepth. A lower recess 40 is also introduced on the bottom of the lowerjoining lip 10. The lower recess 40 will allow the lower joining lip 10to be bent downwards during the assembly, without having to touch theunderlying surface.

What is claimed is:
 1. Flooring material intended to be joinedvertically comprising floor boards with an essentially square,rectangular or rhombodial shape, which floor boards comprise edges,horizontal lower side and a horizontal decorative upper surface, wherebythe floor boards further comprise lower joining lips at two adjacentedges while the two remaining edges are provided with upper joininglips, the lower joining lips and upper joining lips each having a shapeto permit assembly in a vertical direction, wherein the lower joininglips are provided with essentially vertical lower lip surfaces arrangedparallel to the closest edge which lower lip surfaces are intended tointeract with mainly vertical upper lip surfaces arranged on the upperjoining lips so that two joined adjacent floor boards are lockedtogether in a horizontal direction and that the joining lips areprovided with one or more heels intended to snap join with recessesadapted thereto which, by being provided with essentially horizontallocking surfaces, limits vertical movement between two joined adjacentfloor boards, whereby the floor boards are joinable by pressingvertically downwards a first floor board with respect a second floorboard to mate the joining lips of the first floor board with the joininglips of the second floor board.
 2. Flooring material intended to bejoined vertically according to claim 1, characterized in that the jointbetween two floor boards (1) joined together includes fitting surfaceswhich are comprises by the horizontal locking surfaces on the recesses(32) and the heels (31), the vertical upper lip surfaces (11) and upperfitting surfaces (3′).
 3. Flooring material intended to be joinedvertically according to claim 2, characterized in that the joint betweentwo floor boards (1) joined together also includes cavities (6). 4.Flooring material intended to be joined vertically according to claim 3,characterized in that the heel (31) is constituted by a resilient partwhich is arranged in a cavity (6).
 5. Flooring material intended to bejoined vertically according to claim 3, characterized in that the recess(32) is constituted by a resilient part (7) which is arranged in acavity (6).
 6. Flooring material intended to be joined verticallyaccording to claim 4, characterized in that the resilient part isconstituted by an extruded thermoplastic profile.
 7. Flooring materialintended to be joined vertically according to claim 4, characterized inthat the resilient part (7) is constituted by a profile made ofthermosetting resin.
 8. Flooring material intended to be joinedvertically according to claim 4, characterized in that the resilientpart (7) is constituted by a profile made of metal.
 9. Flooring materialintended to be joined vertically according to claim 5, characterized inthat the resilient part is constituted by an extruded thermoplasticprofile.
 10. Flooring material intended to be joined verticallyaccording to claim 5, characterized in that the resilient part (7) isconstituted by a profile made of thermosetting resin.
 11. Flooringmaterial intended to be joined vertically according to claim 5,characterized in the resilient part (7) is constituted by a profile madeof metal.
 12. Flooring material intended to be joined verticallyaccording to claim 1, wherein the floor boards are joinable by movingthe first floor board straight downward from a plane parallel to a planeof the second floor board into the plane of the second floor board tomate the joining lips of the first floor board with the joining lips ofthe second floor board.
 13. Flooring material comprising at least afirst floor board and an adjacent second floor board, the first andsecond floor boards comprising edges permitting joining through verticalmovement, wherein a joint between the first and second floor boardscomprises: fitting surfaces, including at least partially inclinedvertical locking surfaces on recesses and heels and upper fittingsurfaces, such that the joint between the first and second floor boardscomprises a plurality of cavities, the first floor board comprising atleast one lower joining lip, the lower joining lip comprising anessentially vertical lower lip surface arranged parallel to the closestedge, and such that a lower lip surface the first floor board mayinteract with a mainly vertical upper lip surface arranged on an upperjoining lip of the second floor board to lock the first and second floorboards together in a horizontal direction, wherein the joining lipscomprise at least one heel, adapted to snap join with the recess bymeans of the at least partially inclined vertical locking surfaces,whereby the vertical movement between two joined adjacent floor boardsis limited.
 14. Flooring material according to claim 13, wherein thefirst and second floorboards further comprise a core, the coreconsisting essentially of wood fibres or wood particles bonded togetherwith glue, resin or a thermoplastic polymer.
 15. Flooring materialaccording to claim 14, wherein the core consists of 4-6 parts by weightof wood fibres or wood particles and 4-6 parts by weight of athermoplastic polymer.
 16. Flooring material according to claim 14,wherein the core contains an additive to improve the elastic andacoustic properties of the core.
 17. Flooring material according toclaim 14, wherein the joint is wholly made in the core.
 18. Flooringmaterial according to claim 13, further comprising glue between thefirst and second floor boards.
 19. Flooring material according to claim13, wherein the area closest to the joint of the floor boards aretreated with at least one material selected from the group consisting ofresin, wax and lacquer to protect the joint from moisture penetration.20. Flooring material according to claims 13, wherein the floor boardscomprise a decorative upper surface.
 21. Flooring material, according toclaim 20, wherein the decorative upper surface, comprises at least oneselected from the group consisting of a decorative paper impregnatedwith melamine-formaldehyde resin and a decorative thermosettinglaminate.
 22. Flooring material according to claim 20, wherein thedecorative upper surface comprises one selected from the groupconsisting of an acrylic foil, a foil of a polyolefin, a foil of apolyolefin derivative, an acrylic lacquer, and a lacquer of apolyolefin.
 23. Flooring material according to claim 20, wherein thedecorative upper surface comprises a polyolefin derivative.